Kevin Cook at the Bloomington Stock Center is funded by the National Center for Research Resources to generate chromosomal deletions. This ongoing project aims to maximize genome deletion coverage and to subdivide the genome further with deletion breakpoints. Deletions with BSC numbers greater than 99 were generated using the FRT-bearing transposable element insertions from Exelixis, Inc. (Thibault et al.) by the methods of Parks et al. These deletions have molecularly mapped endpoints and share the isogenic background of the Exelixis deletions and insertions. Reference: Cook et al. 2012 (see also Roote & Russell 2012)

Deletions with lower BSC numbers were generated by the Hybrid Element Insertion (HEI) method described in Parks et al., 2004 (exceptions noted below) and are not isogenic. These deletions were induced by P-element transposase in the presence of trans-heterozygous P-element insertions. The HEI model predicts that one deletion endpoint will correspond to the insertion site of one of the starting insertions and the other endpoint will map near the other insertion site. The precise endpoints have not been characterized molecularly. Df(3L)BSC1, Df(3L)BSC2 and Df(2L)BSC7 were generated by irradiation mutagenesis and are not isogenic. Their breakpoints have been characterized cytologically, but not molecularly.